/*- * Copyright (c) 2008-2009 Robert N. M. Watson * Copyright (c) 2011 Jonathan Anderson * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * Test routines to make sure a variety of system calls are or are not * available in capability mode. The goal is not to see if they work, just * whether or not they return the expected ECAPMODE. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "cap_test.h" #define CHECK_SYSCALL_VOID_NOT_ECAPMODE(syscall, ...) do { \ errno = 0; \ (void)syscall(__VA_ARGS__); \ if (errno == ECAPMODE) \ FAIL("capmode: %s failed with ECAPMODE", #syscall); \ } while (0) int test_capmode(void) { struct statfs statfs; struct stat sb; long sysarch_arg = 0; int fd_close, fd_dir, fd_file, fd_socket, fd2[2]; int success = PASSED; pid_t pid, wpid; char ch; /* Open some files to play with. */ REQUIRE(fd_file = open("/tmp/cap_capmode", O_RDWR|O_CREAT, 0644)); REQUIRE(fd_close = open("/dev/null", O_RDWR)); REQUIRE(fd_dir = open("/tmp", O_RDONLY)); REQUIRE(fd_socket = socket(PF_INET, SOCK_DGRAM, 0)); /* Enter capability mode. */ REQUIRE(cap_enter()); /* * System calls that are not permitted in capability mode. */ CHECK_CAPMODE(access, "/tmp/cap_capmode_access", F_OK); CHECK_CAPMODE(acct, "/tmp/cap_capmode_acct"); CHECK_CAPMODE(bind, PF_INET, NULL, 0); CHECK_CAPMODE(chdir, "/tmp/cap_capmode_chdir"); CHECK_CAPMODE(chflags, "/tmp/cap_capmode_chflags", UF_NODUMP); CHECK_CAPMODE(chmod, "/tmp/cap_capmode_chmod", 0644); CHECK_CAPMODE(chown, "/tmp/cap_capmode_chown", -1, -1); CHECK_CAPMODE(chroot, "/tmp/cap_capmode_chroot"); CHECK_CAPMODE(connect, PF_INET, NULL, 0); CHECK_CAPMODE(creat, "/tmp/cap_capmode_creat", 0644); CHECK_CAPMODE(fchdir, fd_dir); CHECK_CAPMODE(getfsstat, &statfs, sizeof(statfs), MNT_NOWAIT); CHECK_CAPMODE(link, "/tmp/foo", "/tmp/bar"); CHECK_CAPMODE(lstat, "/tmp/cap_capmode_lstat", &sb); CHECK_CAPMODE(mknod, "/tmp/capmode_mknod", 06440, 0); CHECK_CAPMODE(mount, "procfs", "/not_mounted", 0, NULL); CHECK_CAPMODE(open, "/dev/null", O_RDWR); CHECK_CAPMODE(readlink, "/tmp/cap_capmode_readlink", NULL, 0); CHECK_CAPMODE(revoke, "/tmp/cap_capmode_revoke"); CHECK_CAPMODE(stat, "/tmp/cap_capmode_stat", &sb); CHECK_CAPMODE(symlink, "/tmp/cap_capmode_symlink_from", "/tmp/cap_capmode_symlink_to"); CHECK_CAPMODE(unlink, "/tmp/cap_capmode_unlink"); CHECK_CAPMODE(unmount, "/not_mounted", 0); /* * System calls that are permitted in capability mode. */ CHECK_SYSCALL_SUCCEEDS(close, fd_close); CHECK_SYSCALL_SUCCEEDS(dup, fd_file); CHECK_SYSCALL_SUCCEEDS(fstat, fd_file, &sb); CHECK_SYSCALL_SUCCEEDS(lseek, fd_file, 0, SEEK_SET); CHECK_SYSCALL_SUCCEEDS(msync, &fd_file, 8192, MS_ASYNC); CHECK_SYSCALL_SUCCEEDS(profil, NULL, 0, 0, 0); CHECK_SYSCALL_SUCCEEDS(read, fd_file, &ch, sizeof(ch)); CHECK_SYSCALL_SUCCEEDS(recvfrom, fd_socket, NULL, 0, 0, NULL, NULL); CHECK_SYSCALL_SUCCEEDS(setuid, getuid()); CHECK_SYSCALL_SUCCEEDS(write, fd_file, &ch, sizeof(ch)); /* * These calls will fail for lack of e.g. a proper name to send to, * but they are allowed in capability mode, so errno != ECAPMODE. */ CHECK_NOT_CAPMODE(accept, fd_socket, NULL, NULL); CHECK_NOT_CAPMODE(getpeername, fd_socket, NULL, NULL); CHECK_NOT_CAPMODE(getsockname, fd_socket, NULL, NULL); CHECK_NOT_CAPMODE(fchflags, fd_file, UF_NODUMP); CHECK_NOT_CAPMODE(recvmsg, fd_socket, NULL, 0); CHECK_NOT_CAPMODE(sendmsg, fd_socket, NULL, 0); CHECK_NOT_CAPMODE(sendto, fd_socket, NULL, 0, 0, NULL, 0); /* * System calls which should be allowed in capability mode, but which * don't return errors, and are thus difficult to check. * * We will try anyway, by checking errno. */ CHECK_SYSCALL_VOID_NOT_ECAPMODE(getegid); CHECK_SYSCALL_VOID_NOT_ECAPMODE(geteuid); CHECK_SYSCALL_VOID_NOT_ECAPMODE(getgid); CHECK_SYSCALL_VOID_NOT_ECAPMODE(getpid); CHECK_SYSCALL_VOID_NOT_ECAPMODE(getppid); CHECK_SYSCALL_VOID_NOT_ECAPMODE(getuid); /* * Finally, tests for system calls that don't fit the pattern very well. */ pid = fork(); if (pid >= 0) { if (pid == 0) { exit(0); } else if (pid > 0) { wpid = waitpid(pid, NULL, 0); if (wpid < 0) { if (errno != ECAPMODE) FAIL("capmode:waitpid"); } else FAIL("capmode:waitpid succeeded"); } } else FAIL("capmode:fork"); if (getlogin() == NULL) FAIL("test_sycalls:getlogin %d", errno); if (getsockname(fd_socket, NULL, NULL) < 0) { if (errno == ECAPMODE) FAIL("capmode:getsockname"); } /* XXXRW: ktrace */ if (pipe(fd2) == 0) { close(fd2[0]); close(fd2[1]); } else if (errno == ECAPMODE) FAIL("capmode:pipe"); /* XXXRW: ptrace. */ /* sysarch() is, by definition, architecture-dependent */ #if defined (__amd64__) || defined (__i386__) CHECK_CAPMODE(sysarch, I386_SET_IOPERM, &sysarch_arg); #else /* XXXJA: write a test for arm */ FAIL("capmode:no sysarch() test for current architecture"); #endif /* XXXRW: No error return from sync(2) to test. */ return (success); }